Non-Hermitian fermions with effective mass
- URL: http://arxiv.org/abs/2302.04706v1
- Date: Thu, 9 Feb 2023 15:45:01 GMT
- Title: Non-Hermitian fermions with effective mass
- Authors: F. C. E. Lima, L. N. Monteiro, and C. A. S. Almeida
- Abstract summary: In seeking a Schr"odinger-like theory with PT symmetry is appropriate to assume a complex potential.
In seeking a Schr"odinger-like theory with PT symmetry is appropriate to assume a complex potential.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: In this work, we readdress the Dirac equation in the position-dependent mass
(PDM) scenario. Here, one investigates the quantum dynamics of non-Hermitian
fermionic particles with effective mass assuming a $(1+1)$-dimension flat
spacetime. In seeking a Schr\"{o}dinger-like theory with PT symmetry is
appropriate to assume a complex potential. This imaginary interaction produces
an effective potential purely dependent on mass distribution. Furthermore, we
study the non-relativistic limit by adopting the Foldy-Wouthuysen
transformation. As a result, that limit leads to an ordering equivalent to the
ordering that describes abrupt heterojunctions. Posteriorly, particular cases
of mass distribution also were analyzed. Thus, interesting results arise for
the case of a linear PDM, which produces an effective harmonic oscillator and
induces the emergence of bound states. For a hyperbolic PDM, an effective
potential barrier emerges. However, in this case, the fermions behave as free
particles with positive-defined energy.
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